Schacht escorted me to a storage room unlike any I’ve visited at a research laboratory. Stacked on a countertop were cocktail mixers: cranberry juice, pineapple juice, Fever-Tree pink-grapefruit soda. Inside a wooden cupboard were shelves of alcohol: Chardonnay, Zinfandel, Tito’s vodka, Jose Cuervo tequila, Mount Gay rum. Where another lab might have pipettes, this one had shot glasses. Schacht had agreed to put me through a cue-reactivity test—which exposes participants to a drug to see how strongly they want it—and to image parts of my brain involved in cravings for alcohol. Before the test, his staff will ask participants what they like to drink. (When participants have specified an ultra-top-shelf liquor, Schacht has been known to ask, “O.K., how often do you actually drink that?”)
My drink of choice is a Negroni. Across the hall from the storage room, I sat down at a table with an iPad on it. Melina Kilen, a disarmingly confident research assistant in a blue sweater and long earrings, arrived with a tray of bartending supplies. She unscrewed the cap from a bottle of gin, poured a shot into a glass over ice, and added sweet vermouth and Campari. I watched the liquid change from clear to golden to amber. Finally, she ran an orange peel around the rim, dropped it into the drink, and left the room.
Cartoon by Patrick McKelvie
A man’s voice emanated from a nearby laptop: “When you hear a high tone”—ding!—“pick up the glass, bring it to your nose, and smell the beverage. When you hear a low tone”—dong!—“stop smelling the beverage and move the glass away from your nose. Do not drink!” For five minutes, I followed instructions, inhaling the drink’s bitter and bright aromas and then putting the glass down again. I was hungry and tired, having flown in late the previous night, and I was surprised that even in a laboratory I wanted to take a sip. Then the test was over; the untouched Negroni was rather cruelly taken away.
On the iPad, I answered some questions. The drink was alluring, I wrote, but not in an all-consuming way. In contrast, one of Schacht’s trial participants, a former I.C.U. nurse whom I’ll call Susan, told me that her cue-reactivity test was “torture.” She remembered sniffing a glass of wine for what seemed like forever. “I wanted that drink so bad,” she said. Before the trial, she’d often have a bottle of wine and a margarita or two per night.
Addiction is more than a subjective sensation; its patterns can be observed in the brain. Schacht told me that when specific brain regions respond more to alcohol than to, say, food, that’s “very predictive of alcohol-use disorder.” He led me to a nearby building that housed MRI scanners. After changing into scrubs, I lay on a padded table that glided into a cylindrical machine. I was holding a remote control that allowed me to rate the strength of my urge to consume alcohol. “Thumb for extreme,” a technician told me. “Pinkie for none.”
For roughly an hour, I was shown images on a screen. I gazed at beautiful landscapes and abstract paintings to establish a baseline, but most of the images were of foods or drinks: glasses of frothy beer nestled in snow; a bottle of red wine next to a bowl of grapes; celery, apples, doughnuts, burgers. Occasionally, a prompt asked me to rate my desire to drink.
Later, on a computer, Schacht pulled up scans that showed what addiction looks like in the brain. Harmful alcohol use is strongly correlated with bright-red splotches in two specific areas, he said. The first, a circle where the hemispheres meet, is the ventral striatum. “That’s where all these dopamine-producing neurons release their dopamine in response to alcohol and other drugs,” Schacht said. Notably, the area is also rich in receptors for naturally occurring GLP-1. The other area, an elongated oval near the front of the brain, is in the medial prefrontal cortex, which is involved in higher-level evaluations of rewards. “It says, ‘Hey, this is something worth chasing!’ ” Schacht told me. Together, the splotches represent a kind of neural signature for craving. “It’s what we hope GLP-1 medications can dampen,” he said.